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Thoracic Ultrasonography Findings and Their Association With Respiratory Pathogens in 221 Young Beef Cattle at Fattening Farms: A Cross‐Sectional Study
No full textInternational audienceThoracic ultrasonography (TUS) could improve antibiotic treatment selection in cattle with respiratory diseases. Hypothesis/Objectives Evaluate the association between respiratory pathogens and consolidations on TUS in feedlot cattle, at both individual and group levels. Animals A total of 221 bulls, aged 8.8 months and weighing 322.5 ± 160 kg, from nine farms. Methods Cross‐sectional study including all data from clinical examinations and TUS collected weekly during the first month on feed. Pathogens were assessed by seroconversion (all animals) and qPCR on nasal swabs (sick animals). At the individual level, the association between pathogen detection and TUS consolidation was investigated using univariate logistic regression, and the ability of consolidation size to differentiate bacterial from non‐bacterial pneumonia was assessed using receiver operating characteristic curves. Principal component analysis identified clusters at the group level based on pathogen detection and TUS results. Results At the individual level, bulls infected with multiple pathogens (odds ratio [OR], 8.1; 95% confidence interval [CI], 2.21–29.8) or a single virus (OR, 5.49; 95% CI, 1.42–21.3) were more likely to have consolidations than those not infected. A total consolidation size > 14 cm 2 in the scanned thoracic region differentiated bacterial from non‐bacterial pneumonia with a sensitivity of 47.8% (95% CI, 36.4–83.3) and specificity of 94.1% (95% CI, 60.0–100.0). These results were consistent at the group level; clustering based on bacterial versus non‐bacterial etiology correlated with the number and size of consolidations. Conclusions and Clinical Importance Consolidation size could help differentiate bacterial from non‐bacterial pneumonia, guiding treatment at both individual and group levels
The human milk endocannabinoidome is preserved by high hydrostatic pressure processing but altered by holder pasteurization
No full textInternational audienceIntroduction: The microbiological safety of donor milk (DM) is commonly ensured by holder pasteurization (HoP, 62.5°C for 30 min) in human milk banks despite its detrimental effects on several bioactive factors. We compared the concentration of twelve endocannabinoid (eCB)-like mediators in raw DM and in DM after holder pasteurization or high hydrostatic pressure processing (HHP, 350 MPa at 38°C), a non-thermal substitute for DM pasteurization.Methods: We measured five N-acyl-ethanolamines (NAEs) and seven 2-mono-acyl-glycerols (2-MAGs) in raw-DM, HHP-DM and HoP-DM using high-performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS).Results: HoP-DM and HHP-DM demonstrated comparable concentrations compared with raw DM of 2-MAGs as well as for N-docosapentaenoyl-ethanolamine (DHEA, an NAE). However, four other NAEs, including N-arachidonoyl-ethanolamine (AEA), N-palmitoyl-(PEA), N-oleoyl -ethanolamine (OEA) and N-linoleoyl-ethanolamine (LEA) were significantly increased by HoP.Conclusion: Our study suggests that HHP-DM may more suitable than HoP-DM to improve the development of preterm infants through the preservation of milk eCB mediators at level close to their initial levels in raw DM
A bovine model of rhizomelic chondrodysplasia punctata caused by a deep intronic splicing variant in the GNPAT gene
No full textInternational audienceBackground Genetic defects that occur naturally in livestock species provide valuable models for investigating the molecular mechanisms underlying rare human diseases. Livestock breeds are subject to the regular emergence of recessive genetic defects due to genetic drift and recent inbreeding. At the same time, their large population sizes provide easy access to case and control individuals and to massive amounts of pedigree, genomic and phenotypic information recorded for management and selection purposes. In this study, we investigated a lethal form of recessive chondrodysplasia observed in 21 stillborn calves of the Aubrac beef cattle breed. Results Detailed examinations of three affected calves revealed proximal limb shortening, epiphyseal calcific deposits, and other pathological signs consistent with human rhizomelic chondrodysplasia punctata, a rare peroxisomal disorder caused by recessive variants in one of five genes ( AGPS, FAR1 , GNPAT , PEX5, and PEX7 ). Using homozygosity mapping, whole genome sequencing of two affected individuals, and filtering for variants found in 1867 control genomes, we reduced the list of candidate variants to a single deep intronic substitution in GNPAT (NC_037355.1:g.4039268G > A on chromosome 28 of the ARS-UCD1.2 bovine genome assembly). For verification, we performed large-scale genotyping of this variant using a custom SNP array and found a perfect genotype–phenotype correlation in 21 cases and 26 of their parents, and a complete absence of homozygotes in 1195 unaffected Aubrac controls. The g.4039268A allele segregated at a frequency of 2.6% in this population and was absent in 375,535 additional individuals from 17 breeds. Then, using in vivo and in vitro analyses, we demonstrated that the derived allele activates cryptic splice sites within intron 11 resulting in abnormal transcripts. Finally, by mining the wealth of records available in the French bovine database, we also reported suggestive effects on juvenile mortality (and not just stillbirth) in homozygotes and on muscle development in heterozygotes, which merit further investigation. Conclusions We report the first spontaneous large animal model of rhizomelic chondrodysplasia punctata and provide a diagnostic test to select against this defect in cattle. Our work also brings interesting insights into the molecular consequences of complete or partial GNPAT insufficiency in mammals
Generation of a compound heterozygous ABCA4 rat model with pathological features of STGD1
No full textInternational audienceThe ABCA4 protein plays an essential role in mammalian vision, ensuring the correct localization of all-trans-retinal within the visual cycle. Mutations in the ABCA4 gene are responsible for the juvenile maculopathy, Stargardt disease (STGD1). We investigated the most common variant underlying STGD1 phenotype in a rat model carrying the ortholog to the human c.5882G > A/p.(Gly1961Glu) (G1961E) in ABCA4. While the pathogenicity of this variant has recently been questioned, we examine here whether the ortholog rat variant is associated with vitamin A toxicity in the retina. By crossing the rat line with a rat line deficient in ABCA4 protein, we reveal a more pathogenic phenotype in line with compound heterozygosity, making the model suitable for testing of gene, cell and pharmacological therapies
Guillain-Barré syndrome in patients with Charcot-Marie-Tooth type 1A disease, probably a non-random association
No full textInternational audienceObjective. To describe four cases of Charcot-Marie-Tooth disease type 1A (CMT1A) who developed Guillain-Barré syndrome (GBS), respectively the most frequent genetic and inflammatory neuropathies.Methods. We described the patients’ clinical and electrodiagnostic characteristics.Results. Our CMT1A patients developed typical GBS at various ages (3 to 76 years). GBS-related clinical manifestations were different within patients, with various severity degrees of seve (weakness, respiratory failure). Nerve conduction studies revealed more severe demyelinating features than expected in patients with no CMT1A. High cerebrospinal fluid protein level was found in 3 patients. GBS outcome was mainly good, although some patients only slowly improved.Conclusions. Our cases are close to the previously described cases of acute worsening in CMT1A, and presented with many electrophysiological features of GBS. Overall, GBS prognosis does not seem worse in CMT1A patients than in other patients. If GBS and CMT1A were independent, the expected frequency of co-occurrence of GBS and CMT1A in our two French regions should be 1 case every 137 years. As we observed 4 cases in only 5 years, we suspect that CMT1A is a risk factor of GBS.Significance. These cases bring further evidence for a non-random link between inflammatory and genetic neuropathies
Preferential localization of Escherichia coli in dairy emulsions: Influence of milk lipid droplets surface composition on bacterial adhesion
No full textInternational audienceIn food emulsions such as raw milk, the lipid droplets exhibit an interfacial layer possibly the site of interactions with bacteria, including the shiga toxin-producing Escherichia coli (STEC). Some pathogenic E. coli strains can adhere to intestinal cells after ingestion or to ligands that could modulate their pathogenicity such as those present at the surface of emulsion lipid droplets. The objectives of this study were to investigate the preferential localization of E. coli cells, AEEC 4315-A strain belonging to the O26:H11 serotype, as a function of the surface composition of emulsion lipid droplets i.e. milk fat globule membrane (MFGM) surrounding raw milk fat globules, milk polar lipids or whole milk proteins. The emulsions were artificially spiked with E. coli from an overnight culture in Brain Heart Infusion broth. Then, the E. coli cells were enumerated in the lipid droplet enriched creams and in the skimmed phases recovered after centrifugation. The localization of the E. coli cells in the creams was observed by confocal laser scanning microscopy (CLSM). This study revealed the role played by the surface properties of dairy lipid droplets on the adhesion of E. coli. For milk fat globules, the concentrations of E. coli in the creams were about 10 times higher than in the aqueous phase. In the processed emulsions, E. coli cells were concentrated in the aqueous phase. The CLSM images showed the adhesion of E. coli to the MFGM containing glycoproteins and their mobility as a function of time in the aqueous phase surrounding lipid droplets. This study provided additional scientific information supporting a specific affinity of E. coli for the MFGM of raw milk fat globules
Démarche médico-légale en cas de maltraitance bovine
No full textInternational audienceCet article, principalement centré sur l’espèce bovine, a pour objectif de fournir quelques éléments pour guider les vétérinaires dans la gestion des cas de maltraitance, en particulier les principales constatations post-mortem liées à la négligence, celle-ci étant la principale maltraitance rencontrée dans les élevages de bovins. La gestion de ces cas exige en effet, de la part du praticien, une certaine expertise technique, scientifique et rédactionnelle en matière d’autopsie. Il doit documenter précisément le contexte de la mort du bovin, les lésions externes et internes telles que la cachexie, la déshydratation, les plaies ou les fractures. Un rapport détaillé doit être rédigé afin de fournir des preuves tangibles pour les enquêtes médico-légales
Lésions nécropsiques et stratégies préventives dans un cas d'urolithiase bovine
No full textInternational audienceObstructive urolithiasis, although sporadic, is a condition with a poor prognosis, particularly in fattening male cattle. This clinical case presents the macroscopic lesions observed in a 14-month-old Parthenais bull that suddenly died in transit to the slaughterhouse. Necropsy revealed renal urolithiasis associated with sub-perforating ulcerative cystitis, extensive fibrino-necrotic urethritis and acute fibrinous peritonitis, leading to fatal septic shock. Urolithiasis was suspected to be of dietary origin (struvite), favoured by nutritional imbalances and inadequate water intake. The discussion covers the predisposing factors (alkaline urine pH, unbalanced ration, low water consumption) and preventive measures, such as adjusting the mineral ration, increasing the intake of quality fodder, and using anionic salts to acidify the urine. This case highlights the importance of prevention in breeding to reduce the risk of recurrence and economic losses.Les urolithiases obstructives, bien que sporadiques, constituent une affection au pronostic sombre, particulièrement chez les bovins mâles en engraissement. Ce cas clinique présente les lésions macroscopiques observées chez un broutard Parthenais de 14 mois, mort brutalement en transit vers l’abattoir. L’autopsie a révélé des calculs rénaux associés à une cystite ulcéreuse sub-perforante, une urétrite fibrino-nécrotique extensive et une péritonite fibrineuse aiguë, responsable d’un choc septique fatal. L’origine alimentaire des calculs (struvite) est suspectée, favorisée par des déséquilibres nutritionnels et une hydratation insuffisante. La discussion aborde les facteurs prédisposants(pH urinaire alcalin, ration déséquilibrée, faible consommation d’eau) et les mesures préventives, telles que l’ajustement de la ration minérale, l’augmentation de l’apport en fourrages de qualité et l’utilisation de sels anioniques pour acidifier l’urine. Ce cas met en évidence l’importance de la prévention en élevage pour réduire les risques de récidive et les pertes économique
Les arthopodes ectoparasites de reptiles : principales espèces et stratégies de lutte
No full textLes problèmes dermatologiques font partie des motifs de consultation les plus fréquents chez les reptiles de particuliers, ophidiens, sauriens ou chéloniens. Dans le diagnostic différentiel, il est important de prendre en compte les ectoparasites et en particulier les arthropodes qui sont les plus communément observés. Ils seront ici divisés en quatre catégories : les tiques, les acariens microscopiques, les diptères piqueurs et les agents de myiases. Après avoir présenté les différents types d’arthropodes ectoparasites et leurs hôtes préférentiels, les moyens de lutte seront abordés. L’étude bibliographique réalisée dans cette thèse montre une véritable évolution dans les traitements avec une tendance à passer de molécules d’origine phytosanitaire vers des molécules plus récentes et plus sûres, ainsi que l’émergence de la lutte biologique. Des tableaux récapitulatifs ont été réalisés pour chaque groupe de reptiles afin de choisir les molécules les plus appropriées au type d’infestation observé
Profil thérapeutique comparé de la capromoréline et de la mirtazapine
No full textNational audienceLa capromoréline et la mirtazapine sont deux agents pharmacologiques utilisés pour stimuler l'appétit chez les chats, en particulier ceux qui souffrent d'une maladie chronique (cancer, insuffisance rénale par exemple), mais aucune étude n'a comparé leurs effets dans les mêmes conditions dans cette espèce. Leur mécanisme d'action diffère, tout comme leur mode d'administration et leur profil d'efficacité